Fireball
First welcome to the village. Great place to be. Next welcome to the addiction also a great place to be.
1) When I finish a piece that shows a line or the edges of BB I normally frame them. It adds to the overall appearance of the project.
2) Watco, Danish, Tung oils and stains can all be top coated with what your wish, as long as you let them dry completely. Some oils take longer to dry then others depending on weather conditions. I normally top coat my stuff with poly giving it plenty of time to dry between coats.
3) Normally I start in the middle. This depends on the pattern though. If there are area that are going to be very delicate when cut, I cut them first, then tape the cut outs back into the board for strength.
4) Can't help you with this one. I have an EX-21 and the upper arm lifts up out of the way. Thinking back to my older saws, I did not have problems feeding the blades through the holes most of the time. Someone might give you better answers but would be nice to know what saw your working with.
Remember the important things, have fun, relax and enjoy.